DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Claims 81-87 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 08/05/2026. The applicant argues, on pp. 7-8 of the response to restriction, that the amendments to claim 81 make the claim commensurate in scope with claim 56, thereby rendering the requirement for restriction moot. The examiner respectfully disagrees. As amended the process does not require that the distal flame holder is formed from essentially metal parts and the product does not require that the pilot burner is continuous or that the continuous pilot burner and the distal flame holder at least partially include shared structure. Therefore, in the amended form the process can be practiced by a materially different apparatus, one without a distal flame holder formed from essentially metal parts, and the apparatus can be used to practice a different process, one without a continuous pilot burner and where the pilot burner and the distal flame holder do not at least partially include shared structure. Additionally, as stated in the requirement for restriction the two inventions would require different fields and search and as such the restriction is maintained.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 58, 61, and 78 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 58 requires “pilot fuel passages” and “the pilot flame”, it is unclear if the pilot flame passages are part of or related to the pilot burner claimed in claim 56 and if “the pilot flame” is the same pilot flame claimed in independent claim 56. For the purposes of examination the structures are interpreted as being the same.
Claim 61 requires that “the metal parts comprise stainless steel” the open ended transitional phrase “comprise” is incompatible with the “consisting essentially of metal parts” claimed in claim 56 because “comprise” allows for an unlimited amount of structure in addition to stainless steel whereas “consisting essentially of” does not.
Claim 78 requires “a mixing tube” and related structure in lines 1-3. The mixing tube is already introduced in independent claim 56, therefore it is unclear if the applicant is introducing a new mixing tube or referring back to the mixing tube already claimed. For the purposes of examination the claim is interpreted as referring back to the mixing tube already claimed.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 56-57, 65, 67-70, 73, and 77-80 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Stephens et. al (US 2004/0018461 A1).
With respect to claim 56 Stephens discloses a low NOx burner, comprising: a main fuel nozzle [reference character 24] disposed at a proximal position in a furnace and configured to output a main fuel into a combustion air stream [the air enters through 37 also see Fig. 6B]; a mixing tube [reference character 12] disposed to receive the main fuel and combustion air stream into a proximal end of the mixing tube and to output mixed main fuel and combustion air at a distal end of the mixing tube: a pilot burner [reference character 86] disposed at a distal position and configured to support a pilot flame to initiate combustion of the mixed main fuel and combustion air; and a distal flame holder [reference character 20] positioned to receive the mixed main fuel and combustion air, and configured to hold a combustion reaction of the mixed main fuel and combustion air, wherein the distal flame holder consists essentially of metal parts [see “metallic burner tip” in paragraph 122].
With respect to claim 57 Stephens discloses that the pilot burner and the distal flame holder at least partially share the same structure [see Fig. 11].
With respect to claim 65 Stephens discloses a combustion air source configured to provide the combustion air stream [see paragraph 0072].
With respect to claim 67 Stephens discloses the combustion air source is configured to cause the stream of combustion air to educe flue gas into the proximal end of the mixing tube; and wherein the mixed main fuel and combustion air output at the distal end of the mixing tube includes mixed main fuel, combustion air, and flue gas [see paragraph 0074].
With respect to claim 68 Stephens discloses that the educing of the flue gas into the proximal end of the mixing tube comprises internal flue gas recirculation [see Fig. 1].
With respect to claim 69 Stephens discloses a natural draft combustion air source configured to provide the combustion air stream [see paragraph 0079].
With respect to claim 70 Stephens does not explicitly disclose that the low NOx burner is configured as a flare; however, the limitation is interpreted as intended use where a person having ordinary skill in the art would recognize that the burner taught by Stephens could be used as a flare and therefore meets the intended use limitations of the claim.
With respect to claim 73 Stephens discloses that the low NOx burner is configured as a boiler burner [paragraph 0071].
With respect to claim 77 Stephens discloses a mounting flange [see annotated Fig. below] configured to mount the low NOx burner to the furnace.
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With respect to claim 78 Stephens discloses a mixing tube [reference character 12] disposed to receive the main fuel and combustion air stream into a proximal end of the mixing tube and to output mixed main fuel and combustion air at a distal end of the mixing tube; and one or more legs [see annotated Fig. below] configured to mechanically couple the mixing tube to the mounting flange (via intervening structure).
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With respect to claim 79 Stephens discloses that the mixing tube mechanically supports the distal flame holder [see Fig. 1].
With respect to claim 80 Stephens does not explicitly disclose that the pilot burner is configured to be a continuous pilot burner, the continuous pilot burner being configured to maintain combustion of the mixed main fuel and combustion air; however, the limitation is interpreted as a functional limitation, where the prior art need only be capable of satisfying the required function. In this case a person having ordinary skill in the art would recognize that the pilot burner could be operated continuously as needed.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 59 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1) in view of Hepburn (US 1,788,716).
With respect to claim 59 Stephens does not disclose that the pilot burner is a premix pilot burner supporting the pilot flame by combustion of a premixed mixture of pilot fuel and combustion air.
Hepburn discloses a burner system having a main burner mixing [reference character 30] and pilot burners [reference character 40] where the pilot burner is premixed [pp. 2 lines 4-6].
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the pilot burner system taught by Stephens by providing a premixed fuel/air mixture, as taught by Hepburn, in order to ensure complete combustion of the pilot fuel.
Claim(s) 61 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1).
With respect to claim 61 Stephens does not disclose that the metal parts comprise stainless steel; however, since stainless steel is a commonly used burner material it would have been obvious to one having ordinary skill in the art at the time of the filing date of the invention to form the flame holder from stainless steel, since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416.
Claim(s) 62 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1) in view of Andrews et. al (US 1,817,911).
With request to claim 62 Stephens does not disclose that the distal flame holder comprises a swirler.
Andrews discloses a burner having a distal flame holder [reference character 55] in the form of a swirler which spreads out the flame and results in a condition of extreme turbulence [pp. 3 lines 5-31] resulting in the ability to stabilize flames at high flow rates and flow velocities.
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the flame holder taught by Stephens by including a distal swirler, as taught by Andrews, in order to stabilize flames at high flow rates and flow velocities.
Claim(s) 63-64 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1) in view of Bigelow et. al (US 5,129,226).
With respect to claim 63 Stephens does not disclose that the distal flame holder comprises a V-gutter.
Bigelow discloses a combustor having a flame stabilizer [see Fig. 1] where the flame holder comprises a V-gutter [reference character 40].
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the flame holder taught by Stephens by including a V-gutter, as taught by Bigelow, in order to stabilize flames at high flow rates and flow velocities.
With respect to claim 64 the combination of Stephens and Bigelow disclose that the V-gutters define crenelated edges [see Fig. 1].
Claim(s) 71-72 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1) in view of Haye et. al (US 3,868,211).
With respect to claim 71 Stephens does not disclose a forced draft combustion air source configured to provide the combustion air stream.
Haye discloses a burner system having a main burner [reference character 23] and a forced draft system using a blower [reference characters 20-21] for supplying combustion air.
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the pilot burner system taught by Stephens by providing a blower, as taught by Haye, for supplying combustion air in order to ensure an adequate supply of air and increase the amount of air as required.
With respect to claim 72 the combination of Stephens and Haye disclose that the forced draft combustion air source comprises a blower [see reference characters 20-21 of Haye].
Claim(s) 74-76 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stephens et. al (US 2004/0018461 A1) in view of Trede (US 2,149,477).
With respect to claim 74 Stephens does not disclose a flame tube boiler configured to output heat from flame tubes carrying combustion products from the furnace, the output heat being arranged to heat water in a shell surrounding the flame tubes.
Trede discloses a flame tube boiler [see Fig. 1] configured to output heat from flame tubes [reference character 18] carrying combustion products from the furnace, the output heat being arranged to heat water in a shell [see Fig. 1] surrounding the flame tubes.
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the system taught by Stephens by using it in a flame tube boiler, as taught by Trede in order to facilitate the production of steam. Note that Stephens discloses that the burner is configured as a boiler burner [see paragraph 0071 of Stephens] however is silent to the boiler structure.
With respect to claim 75 Stephens does not disclose a water tube boiler having water tubes configured to transfer heat from the furnace to water flowing through the water tubes.
Trede discloses a water tube boiler [see Fig. 1] having water tubes [reference characters 5] configured to transfer heat from the furnace to water flowing through the water tubes surrounding the flame tubes.
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the system taught by Stephens by using it in a water tube boiler, as taught by Trede in order to facilitate the production of steam. Note that Stephens discloses that the burner is configured as a boiler burner [see paragraph 0071 of Stephens] but is silent to the boiler structure.
With respect to claim 76 Stephens does not disclose a superheater configured as steam tubes carrying steam, the superheater being disposed in a flue disposed to receive hot combustion products from the combustion reaction.
Trede discloses a boiler [see Fig. 1] having a superheater [reference character 12] configured as steam tubes carrying steam, the superheater being disposed in a flue [reference character 10] disposed to receive hot combustion products [see Fig. 1] from the combustion reaction.
It would have been obvious to one of ordinary skill in the art at the time of the filing date of the invention to modify the system taught by Stephens by using it in a flame tube boiler, as taught by Trede in order to facilitate the production of steam. Note that Stephens discloses that the burner is configured as a boiler burner [see paragraph 0071 of Stephens] but is silent to the boiler structure.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to VIVEK K SHIRSAT whose telephone number is (571)272-3722. The examiner can normally be reached M-F 9:00AM-5:20AM.
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/VIVEK K SHIRSAT/ Primary Examiner, Art Unit 3762
